Chrysler's 3.2 liter V-6 engine was a new design, using aluminum blocks and heads, based on the original 3.5 liter V6; it was discontinued in 2002 to simplify the engine lineup.
These engines could be shipped with a variable intake system, building on Chrysler's work back in the 1950s and 60s (to be fair, other automakers have used variable intake systems). It varies the length of the intake manifold tubes to create a small, but useful, supercharging effect at different engine speeds. In the past, tuning the air tubes for a boost at one engine speed sacrificed power at another; this is similar to variable valve timing in that it avoids choosing one engine speed over another for performance increases.
Bob Sheaves suggested that the 3.2 was derived from the larger 3.5 engine, with creation in this order ("I refer to the development design and components, and not what eventually became production.")
According to Bob, the 3.2 was developed from the 3.5. Willem Weertman’s Chrysler Engines book suggests that the 2.7 was based directly off the 3.5, but should be considered to be in its own engine family.
The following information was provided by Chrysler.
Competitive information from manufacter's press kits and data books.
For those who think the Chrysler 3.5 is made by Mitsubishi, here is a comparison:
@ 6000 / 190 @ 6,400
188 @ 4900 / 190 @ 4,000
Emissions: all use at least one three-way catalytic converter, quad-heated oxygen sensors, EGR, and internal engine features. 3.8 meets Tier 2 bin 5 (federal) and LEV 2 (CA) specs; 4.0 meets Federal tier 2, bin 8 and ULEV1 (CA) specs.
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